From e16f7ec2ad736c438fabcfbbfa03e270e7a96036 Mon Sep 17 00:00:00 2001
From: Breno Viana <brenomfviana@gmail.com>
Date: Thu, 16 Apr 2020 20:01:18 -0300
Subject: [PATCH] improves the initialization function ('new') of the search
 config structure

---
 src/lib.rs  | 28 ++++++++++++++++++----------
 src/main.rs |  4 +---
 2 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/src/lib.rs b/src/lib.rs
index cc047c0..846a7e3 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -18,18 +18,26 @@ pub struct Config {
 
 impl Config {
   /// Gets the arguments, validates them and returns the search configuration.
-  pub fn new(args: &[String]) -> Result<Config, &'static str> {
-    // Check if the arguments are valid
-    match args.len() {
-      3 => { /* Right number of arguments. */ },
-      0 => return Err("how did you do it?"),
-      1 => return Err("you did not enter any arguments."),
-      2 => return Err("you did not enter the filename."),
-      _ => println!("  WARNING: You have entered more arguments than needed."),
+  pub fn new(mut args: std::env::Args) -> Result<Config, &'static str> {
+    // Skip program call
+    args.next();
+    // Get query string from arguments
+    let query = match args.next() {
+      Some(arg) => arg,
+      None => return Err("you did not enter a string."),
+    };
+    // Get query filename from arguments
+    let filename = match args.next() {
+      Some(arg) => arg,
+      None => return Err("you did not enter the filename"),
+    };
+    // Check if the case insensitive variable is active
+    let case_sensitive = env::var("CASE_INSENSITIVE").is_err();
+    // Check if there are still arguments
+    if let Some(_) = args.next() {
+      println!("  WARNING: You have entered more arguments than needed.");
     }
     // Return the search configuration
-    let (query, filename, case_sensitive) =
-      (args[1].clone(), args[2].clone(), env::var("CASE_INSENSITIVE").is_err());
     Ok(Config{ query, filename, case_sensitive })
   }
 }
diff --git a/src/main.rs b/src/main.rs
index 3d4313e..dbafb12 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -10,10 +10,8 @@ use std::process;
 use minigrep::Config;
 
 fn main() {
-  // Get arguments
-  let args: Vec<String> = env::args().collect();
   // Get the search configuration
-  let config = Config::new(&args).unwrap_or_else(|err| {
+  let config = Config::new(env::args()).unwrap_or_else(|err| {
     eprintln!("Problem parsing arguments: {}", err);
     process::exit(1);
   });